Electrochemical cell structure

Abstract

An electrochemical cell structure comprises an anode, a cathode spaced apart from the anode and an electrolyte in ionic communication with each of the cathode and the anode. A single-piece nonconductive frame supports each of the anode, the cathode and the electrolyte and defines a flowpath for working fluids and for byproducts or ionic exchange.

1 . An electrochemical cell structure comprising: 
 an anode;    a cathode spaced apart from said anode;    an electrolyte in ionic communication with each of said anode and said cathode; and    a single-piece nonconductive frame that supports each of said anode, said cathode and said electrolyte and defines at least one flowpath for working fluids and for byproducts of ionic exchange.    
     
     
         2 . An electrochemical cell structure in accordance with  claim 1 , wherein said single-piece nonconductive frame comprises a material having a maximum working temperature in a range between about 60 degrees Celsius to about 120 degrees Celsius.  
     
     
         3 . An electrochemical cell structure in accordance with  claim 1 , wherein said single-piece nonconductive frame comprises a material having a maximum working temperature in a range between about 60 degrees Celsius to about 300 degrees Celsius.  
     
     
         4 . An electrochemical cell structure in accordance with  claim 1 , wherein said electrochemical cell structure is suitable as an alkaline electrolyzer.  
     
     
         5 . An electrochemical cell structure in accordance with  claim 4 , wherein said electrolyte is a liquid alkaline solution.  
     
     
         6 . An electrochemical cell structure in accordance with  claim 5 , wherein said electrolyte is selected from the group consisting of Sodium Hydroxide or Potassium Hydroxide.  
     
     
         7 . An electrochemical cell structure in accordance with  claim 1 , wherein said single-piece nonconductive frame comprises a formed compononent.  
     
     
         8 . An electrochemical cell structure in accordance with  claim 7 , wherein said formed component comprises a molded component.  
     
     
         9 . An electrochemical cell structure in accordance with  claim 1 , wherein said single-piece nonconductive frame comprises a plurality of individual component parts joined together.  
     
     
         10 . An electrochemical cell structure in accordance with  claim 9 , wherein said component parts are joined together using an adhesive.  
     
     
         11 . An electrochemical cell structure in accordance with  claim 9 , wherein said component parts are joined together with at least one of ultrasonic or laser welding.  
     
     
         12 . An electrochemical cell structure in accordance with  claim 9 , wherein said component parts are joined together by melting and cooling.  
     
     
         13 . An electrochemical cell structure in accordance with  claim 1 , wherein said nonconductive frame material comprises a polymer.  
     
     
         14 . An electrochemical cell structure in accordance with  claim 1 , wherein said nonconductive frame comprises a material that is chemically resistant to caustic.  
     
     
         15 . An electrochemical cell structure in accordance with  claim 1 , wherein said nonconductive frame material comprises a hydrolytically stable polymer.  
     
     
         16 . An electrochemical cell structure in accordance with  claim 1 , wherein said nonconductive frame material is selected from the group consisting of polyethylene, fluorinated polymers, polypropylene, polysulfones polyphenyleneoxide, polyphenylenesulfide, polystyrene and combinations thereof.  
     
     
         17 . A cell structure for an alkaline electrolyzer comprising: 
 an anode;    a cathode spaced apart from said anode;    a liquid alkaline electrolyte in ionic communication with each of said anode and said cathode; and    a single-piece nonconductive polymer frame that supports each of said anode, said cathode and said electrolyte and defines at least one flowpath for working fluids and for byproducts of ionic exchange.    
     
     
         18 . A cell structure for an alkaline electrolyzer in accordance with  claim 17 , wherein said single-piece nonconductive polymer frame comprises a material that is chemically resistant to caustic.  
     
     
         19 . A cell structure for an alkaline electrolyzer in accordance with  claim 17 , wherein said single-piece nonconductive polymer frame comprises a hydrolytically stable polymer.  
     
     
         20 . A cell structure for an alkaline electrolyzer in accordance with  claim 17 , wherein said single-piece nonconductive polymer frame comprises a material selected from the group consisting of polyethylene, fluorinated polymers, polypropylene, polysulfones polyphenyleneoxide, polyphenylenesulfide, polystyrene and combinations thereof.  
     
     
         21 . An electrochemical stack comprising: 
 a first end cap having a noncoductive housing and an anode disposed therein;    a second end cap having a noncoductive housing and a cathode disposed therein; and 
 a plurality of repeat plates interposed between said first and said second end caps, each of said repeat plates comprising a nonconductive housing and an electrode insert disposed therein;  
 wherein each of said nonconductive housings of said first end plate, said repeat plates, and said second end plate are joined together to form a single-piece nonconductive frame and define a plurality of flow paths within said electrochemical stack.  
   
     
     
         22 . An electrochemical stack in accordance with  claim 21 , wherein said nonconductive frame comprises a polymer material.  
     
     
         23 . An electrochemical stack in accordance with  claim 21 , wherein said nonconductive frame comprises a material that is chemically resistant to caustic.  
     
     
         24 . An electrochemical stack in accordance with  claim 21 , wherein said nonconductive frame comprises a hydrolytically stable polymer.  
     
     
         25 . An electrochemical stack in accordance with  claim 21 , wherein said nonconductive frame comprises a material selected from the group consisting of polyethylene, fluorinated polymers, polypropylene, and polysulfones.  
     
     
         26 . An electrochemical stack in accordance with  claim 21 , wherein said electrode insert comprises an anode and a cathode and a bipolar plate interposed therebetween.  
     
     
         27 . An electrochemical stack in accordance with  claim 21 , wherein said repeat plate further comprises a first diaphragm and a second diaphragm disposed on opposite sides of said electrode insert to promote separation of gases.  
     
     
         28 . A repeat plate for fabrication of a electrochemical stack, said repeat plate comprising: 
 a single-piece nonconductive frame defining a plurality of flow paths and an electrode frame; and    an electrode assembly disposed within said electrode frame.    
     
     
         29 . A repeat plat in accordance with  claim 28 , wherein said a single-piece nonconductive frame comprises a polymer material.  
     
     
         30 . A repeat plate for fabrication of an alkaline electrolysis stack, said repeat plate comprising: 
 an anode, a cathode and a bipolar plate interposed therebetween, joined together to define an electrode assembly; a single-piece nonconductive frame defining an electrolyte inlet, at least a first flow path in fluid communication with said anode and a second electrolyte flow path in fluid communication with said cathode, an electrode frame that supports said electrode assembly, an oxygen flow path in fluid communication with said anode and terminating in an oxygen outlet and a hydrogen flow path in fluid communication with said cathode and terminating in a hydrogen outlet; a first diaphragm disposed adjacent said anode opposite said bipolar plate to promote electrolyte flow between adjacent repeat plates but to prevent the oxygen from mixing with hydrogen formed at an adjacent repeat plate cathode; a second diaphragm disposed adjacent said cathode opposite said bipolar plate to promote electrolyte flow between adjacent repeat plates but to prevent the hydrogen from mixing with the oxygen formed at an adjacent repeat plate anode; wherein upon introduction of an electrolyte and application of an electric current between adjacent repeat plates, said electrolyte flows into said repeat plate through said electrolyte inlet and to said anode and said cathode through said first and said second electrolyte flow paths respectively, wherein a portion of said electrolyte disassociates into oxygen and hydrogen at said anode and said cathode and flows through said oxygen flow path and said hydrogen flow path respectively.    
     
     
         31 . A repeat plate in accordance with  claim 30 , wherein said single-piece nonconductive frame comprises a polymer.  
     
     
         32 . A repeat plate in accordance with  claim 30 , wherein said single-piece nonconductive frame comprises a hydrolytically stable polymer.  
     
     
         33 . A repeat plate in accordance with  claim 30 , wherein said single-piece nonconductive frame comprises a material that is chemically resistant to caustic.  
     
     
         34 . A repeat plate in accordance with  claim 30 , wherein said single-piece nonconductive frame comprises a material selected from the group consisting of polyethylene, fluorinated polymers, polypropylene, polysulfones polyphenyleneoxide, polyphenylenesulfide, polystyrene and combinations thereof.  
     
     
         35 . An electrochemical stack comprising: 
 a first end cap having a noncoductive housing and an anode disposed therein;    a second end cap having a noncoductive housing and a cathode disposed therein; and 
 a plurality of repeat plates interposed between said first and said second end caps, each of said repeat plates comprising a nonconductive housing and an electrode insert disposed therein;  
 wherein each of said nonconductive housings of said first end plate, said repeat plates, and said second end plate are formed together as a single-piece nonconductive frame and define a plurality of flow paths within said electrochemical stack.  
   
     
     
         36 . An electrochemical stack in accordance with  claim 35 , wherein said nonconductive housings are formed together using a mold.  
     
     
         37 . A method of of electrochemical cell fabrication comprising the steps of: 
 positioning an electrode assembly within a first nonconductive frame piece; and    joining a second nonconductive frame piece to said first nonconductive frame piece to sandwich the electrode assembly therebetween.    
     
     
         38 . A method in accordance with  claim 37 , wherein said method further comprises 
 positioning a diaphragm on a first side of said electrode assembly; and    joining a nonconductive frame piece to said first nonconductive frame piece to sandwich the diaphragm therebetween.    
     
     
         39 . A method in accordance with  claim 38 , wherein said method further comprises 
 positioning a second diaphragm on a second side of said electrode assembly; and    joining a nonconductive frame piece to said second nonconductive frame piece to sandwich the second diaphragm therebetween.    
     
     
         40 . A method of electrochemical cell fabrication comprising the steps of: 
 positioning a plurality of electrode assemblies within a molding apparatus;    enveloping flow channels to and from said electrode assemblies within said molding apparatus;    dispensing a heated nonconductive molding material within said molding apparatus to surround said plurality of electrode assemblies and said enveloped flow channels; and    cooling said heated nonconductive molding material to mechanically bind the electrode assemblies and define the flow channels within a single-piece nonconductive frame.    
     
     
         41 . An electrochemical cell structure comprising: 
 a first electrode assembly;    a second electrode aseembly spaced apart from said first electrode assembly; and    a single-piece nonconductive frame that supports each of said first electrode assembly and said second electrode assembly and defines at least one flowpath for working fluids and for byproducts of ionic exchange.    
     
     
         42 . An electrochemical cell structure in accordance with  claim 41 , wherein said nonconductive frame material comprises a polymer.